A method of reducing coke formation grindability index

Abstract

This invention discloses a method for reducing the grindability index of raw coke. After the carbonization feed is completed, the heating furnace heat load is maintained, and steam or heavy oil is introduced into the furnace tubes. The heated steam or heavy oil is then sent to the carbonization tower. Simultaneously, the carbonization tower is restored to a slightly positive pressure within 30-60 minutes, and the carbonization reaction temperature of the material is maintained to continue the carbonization reaction. Then, the raw coke exiting the carbonization tower is sent to a carbonization furnace or brick kiln for calcination. This invention, based on the raw coke production process and the principles affecting the grindability index of raw coke, produces raw coke with an adjustable grindability index suitable for manufacturers, reducing the time spent by manufacturers in raw material selection.

Description

Technical Field

[0001] This invention belongs to the field of coking production technology, and particularly relates to a method for reducing the grindability index of raw coke. Background Technology

[0002] The concept of grindability index originated from coal and refers to the ease with which coal particles of the same mass can be ground into powder using the same amount of energy. It is an important reference for coal mining companies when selecting crushing processes and equipment, and also a basis for assessing energy consumption within power plants. This index also applies to coking plants. Cost reduction and efficiency improvement are long-term challenges for enterprises, and providing downstream companies with raw materials suitable for their production processes is a problem that raw material preparation manufacturers need to solve.

[0003] Against the backdrop of increasing environmental pressure, the gradual replacement of heavily polluting traditional products with new energy products is an inevitable trend, such as the rapidly developing new energy vehicles. As a component of lithium batteries used in new energy vehicles, there are many suppliers of anode materials. The technical challenge of producing materials that meet the grinding, crushing, and high yield requirements of anode material manufacturers has become an urgent technical problem for these suppliers. However, in the selection of anode material raw materials, downstream manufacturers have not yet found relevant technologies to learn from and typically rely on a wide selection of coke suitable for their own process routes. Summary of the Invention

[0004] In view of the above-mentioned defects in the existing technology, the purpose of this invention is to provide a method for reducing the grindability index of raw coke. Based on the raw coke production process and the principle that affects the grindability index of raw coke, the method prepares raw coke with an adjustable grindability index that is suitable for manufacturers, thereby reducing the time spent by manufacturers in raw material selection.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] This invention provides a method for reducing the grindability index of raw coke. After the carbonization raw material is fed, the heating furnace is kept at its heat load, and the feed is switched to steam or heavy oil. After being heated in the heating furnace, the steam or heavy oil enters the carbonization tower, and the carbonization tower is restored to a slightly positive pressure within 30 to 60 minutes. At the same time, the carbonization reaction temperature of the raw material is maintained to continue the carbonization reaction. Then, the raw coke from the carbonization tower is sent to a carbonization furnace or rotary kiln for heat treatment.

[0007] Preferably, the amount of steam injected is 10-30 wt% of the carbonization raw material feed.

[0008] Preferably, the amount of heavy oil added is 5-15 wt% of the carbonization feedstock.

[0009] Preferably, the micro-positive pressure inside the carbonization tower is 20–50 kPa.

[0010] Preferably, the deep reaction time of the carbonization reaction is 2 to 8 hours.

[0011] Preferably, the carbonization reaction temperature is 450–485°C.

[0012] Preferably, the heat treatment temperature is 450–485°C, and the heat treatment time is 1–2 hours.

[0013] Preferably, the method for reducing the grindability index of raw coke yields a grindability index of 40 to 90.

[0014] The beneficial effects of the rust-proof product for chrome-plated plates and its preparation method provided by this invention are as follows:

[0015] 1. The method of reducing the grindability index of raw coke of the present invention directly controls the grindability index of raw coke by changing the production process route of the raw material manufacturer and extending the degree of carbonization reaction. In the end, the raw materials that meet the needs of downstream manufacturers are prepared, breaking through the traditional method of downstream manufacturers to select raw materials from a wide range of sources, reducing the time spent by manufacturers on raw material selection and hindering the progress of research and development.

[0016] 2. The method for reducing the grindability index of raw coke of the present invention requires the introduction of steam or heavy oil during the process, which can clean the furnace tubes, help prevent coking of the furnace tubes, and greatly reduce the workload of processing the furnace tubes after shutdown. Detailed Implementation

[0017] To better understand the above-mentioned technical solutions of the present invention, the technical solutions of the present invention will be further described below in conjunction with embodiments.

[0018] The method for reducing the grindability index of raw coke according to the present invention involves maintaining the heat load of the heating furnace after the carbonization raw material feeding is completed, switching to steam or heavy oil for continued feeding, and then allowing the steam or heavy oil to enter the carbonization tower after heating in the heating furnace. The carbonization tower is then restored to a slightly positive pressure within 30-60 minutes, while maintaining the carbonization reaction temperature of the raw material to continue the carbonization reaction. The raw coke exiting the carbonization tower is then sent to a carbonization furnace or rotary kiln for heat treatment. The specific process of the present invention is as follows:

[0019] (1) Extend the carbonization reaction time: After the carbonization raw material is fed, keep the heating furnace heating and switch to steam or heavy oil to continue feeding. After being heated by the heating furnace, the steam or heavy oil enters the carbonization tower. Within 30 to 60 minutes, restore the carbonization tower to a slightly positive pressure and maintain the carbonization reaction temperature of the carbonization raw material to continue the carbonization reaction. Among them, the amount of steam injected is 10 to 30 wt% of the carbonization raw material feed amount; the amount of heavy oil added is 5 to 15 wt% of the carbonization raw material feed amount; the slightly positive pressure in the carbonization tower is 20 to 50 kPa; the carbonization reaction temperature is 450 to 485℃; and the deep reaction time of the carbonization reaction is 2 to 8 hours.

[0020] (2) Low-temperature heat treatment: The raw coke from the carbonization tower is fed into a carbonization furnace or rotary kiln at the carbonization reaction temperature of the carbonization raw materials for heat treatment. The heat treatment temperature is 450-485℃ and the heat treatment time is 1-2 hours. The above method can effectively reduce the grindability index of the raw coke.

[0021] Based on the production process of raw coke and the principles affecting the grindability index of raw coke, the grindability index of raw coke is adjusted to a range suitable for downstream manufacturers through the above treatment. Finally, the grindability index of raw coke prepared by this invention is adjustable from 40 to 90.

[0022] The method for reducing the grindability index of raw coke according to the present invention will be further described below with specific examples.

[0023] Example 1

[0024] Using existing coking processes: carbonization reaction temperature 465℃, reaction time 24h, carbonization feed rate 9t / h, carbonization tower pressure 0.5MPa, the final product is raw coke with a grindability index of 128.

[0025] In this embodiment, the grindability index of the raw coke required by downstream manufacturers is 80-90.

[0026] The method adopted was to reduce the grindability index of the raw coke. After the carbonization raw material was fed, the heating furnace continued to heat the furnace tubes, injecting 1.35t of 0.8MPa steam into the furnace tubes every hour. The steam heated by the heating furnace entered the carbonization tower, reducing the pressure in the carbonization tower to 20kPa within 30 minutes and maintaining the carbonization reaction temperature of the raw material. After continuing the deep reaction for 6 hours, the gas injection was stopped, and the process was stopped normally. At this time, the grindability index of the raw coke was 84.

[0027] The raw coke prepared above was fed into a rotary kiln via a belt conveyor for heat treatment. The temperature was raised to 465°C at a heating rate of 5-10°C / min, and then the rotation speed was reduced. After heat treatment for 2 hours, the raw coke was discharged to obtain raw coke with a grindability index of 85.

[0028] Example 2

[0029] Using existing coking processes: carbonization reaction temperature 485℃, reaction time 36h, carbonization feed rate 6t / h, carbonization tower pressure 0.45MPa, the final product is raw coke with a grindability index of 98.

[0030] In this embodiment, the grindability index of the raw coke required by downstream manufacturers is 50-60.

[0031] The method adopted was to reduce the grindability index of the raw coke. After the carbonization raw material was fed, the furnace tubes were kept heated by the heater. 0.6t of heavy oil was injected into the furnace tubes every hour. The heavy oil heated by the heater entered the carbonization tower. The pressure in the carbonization tower was reduced to 30kPa within 30 minutes, and the carbonization reaction temperature of the raw material was maintained. After the deep reaction continued for 2 hours, the addition of heavy oil was stopped, and the process was stopped normally. At this time, the grindability index of the raw coke was 53.

[0032] The raw coke prepared above was fed into a rotary kiln via a belt conveyor for heat treatment. The temperature was raised to 485°C at a heating rate of 5-10°C / min, and then the rotation speed was reduced. After heat treatment for 2 hours, the raw coke was discharged to obtain raw coke with a grindability index of 52.

[0033] Example 3

[0034] Using existing coking processes: carbonization reaction temperature 475℃, reaction time 24h, carbonization raw material feed rate 12t / h, carbonization tower pressure 0.25MPa, the final product is raw coke with a grindability index of 115.

[0035] In this embodiment, the grindability index of the raw coke required by downstream manufacturers is 40-50.

[0036] The method adopted was to reduce the grindability index of the raw coke. After the carbonization raw material was fed, the furnace tubes were kept heated by the heater. 0.6t of heavy oil was injected into the furnace tubes every hour. The heavy oil heated by the heater entered the carbonization tower. The pressure in the carbonization tower was reduced to 50kPa within 60min, and the carbonization reaction temperature of the raw material was maintained. After the deep reaction continued for 2 hours, the addition of heavy oil was stopped, and the process was stopped normally. At this time, the grindability index of the raw coke was 45.

[0037] The raw coke prepared above was fed into a rotary kiln via a belt conveyor for heat treatment. The temperature was raised to 475°C at a heating rate of 5-10°C / min, and then the rotation speed was reduced. After heat treatment for 2 hours, the raw coke was discharged to obtain raw coke with a grindability index of 46.

[0038] Example 4

[0039] Using existing coking processes: carbonization reaction temperature 455℃, reaction time 36h, carbonization feed rate 9t / h, carbonization tower pressure 0.35MPa, the final product is raw coke with a grindability index of 140.

[0040] In this embodiment, the grindability index of the raw coke required by downstream manufacturers is 80-90.

[0041] The method adopted was to reduce the grindability index of the raw coke. After the carbonization raw material was fed, the heating furnace continued to heat the furnace tubes, injecting 2.7t of 0.8MPa steam into the furnace tubes every hour. The steam heated by the heating furnace entered the carbonization tower, reducing the pressure in the carbonization tower to 30kPa within 30 minutes and maintaining the carbonization reaction temperature of the raw material. After continuing the deep reaction for 8 hours, the gas injection was stopped, and the process was stopped normally. At this time, the grindability index of the raw coke was 88.

[0042] The raw coke prepared above is fed into a rotary kiln via a belt conveyor for heat treatment. The temperature is raised to 455°C at a heating rate of 5-10°C / min, and then the rotation speed is reduced. After heat treatment for 2 hours, the raw coke is discharged to obtain raw coke with a grindability index of 90.

[0043] Example 5

[0044] Using existing coking processes: carbonization reaction temperature 450℃, reaction time 36h, carbonization feed rate 10t / h, carbonization tower pressure 0.40MPa, the final product is raw coke with a grindability index of 145.

[0045] In this embodiment, the grindability index of the raw coke required by downstream manufacturers is 85-90.

[0046] The method adopted was to reduce the grindability index of the raw coke. After the carbonization raw material feeding was completed, the heating furnace continued to heat the furnace tubes, injecting 3t of 0.8Mpa steam into the furnace tubes every hour. The steam heated by the heating furnace entered the carbonization tower, reducing the pressure in the carbonization tower to 50kPa within 60min, and maintaining the carbonization reaction temperature of the raw material. After continuing the deep reaction for 6 hours, the gas injection was stopped, and the process was stopped normally. At this time, the grindability index of the raw coke was 85.

[0047] The raw coke prepared above is fed into a rotary kiln via a belt conveyor for heat treatment. The temperature is raised to 450°C at a heating rate of 2-10°C / min, and then the rotation speed is reduced. After calcination for 2 hours, the raw coke is discharged to obtain raw coke with a grindability index of 90.

[0048] Example 6

[0049] Using existing coking processes: carbonization reaction temperature 480℃, reaction time 36h, carbonization feed rate 12t / h, carbonization tower pressure 0.30MPa, the final product is raw coke with a grindability index of 85.

[0050] In this embodiment, the grindability index of the raw coke required by downstream manufacturers is 60-70.

[0051] The method adopted was to reduce the grindability index of the raw coke. After the carbonization raw material was fed, the heating furnace continued to heat the furnace tubes, and 1.8t of heavy oil was injected into the furnace tubes every hour. The heavy oil heated by the heating furnace entered the carbonization tower, and the pressure in the carbonization tower was reduced to 20kPa within 60 minutes. The carbonization reaction temperature of the carbonization raw material was maintained, and the deep reaction continued for 6 hours. Then, the addition of heavy oil was stopped, and the process was stopped normally. At this time, the grindability index of the raw coke was 65.

[0052] The raw coke prepared above was fed into a rotary kiln via a belt conveyor for heat treatment. The temperature was raised to 480°C at a heating rate of 5-10°C / min, and then the rotation speed was reduced. After heat treatment for 1 hour, the raw coke was discharged to obtain raw coke with a grindability index of 68.

[0053] Those skilled in the art should recognize that the above embodiments are merely illustrative of the present invention and are not intended to limit the present invention. Any variations or modifications to the above embodiments that are within the spirit and essence of the present invention will fall within the scope of the claims of the present invention.

Claims

1. A method for reducing the grindability index of raw coke, characterized in that, After the carbonization raw material feeding is completed, the heating furnace heat load is maintained, and the feed is switched to steam or heavy oil. After being heated in the heating furnace, the steam or heavy oil enters the carbonization tower, and the carbonization tower is restored to a slightly positive pressure within 30-60 minutes, while maintaining the carbonization reaction temperature of the raw material to continue the carbonization reaction. Then, the raw coke from the carbonization tower is sent to a carbonization furnace or rotary kiln for heat treatment. The micro-positive pressure inside the carbonization tower is 20–50 kPa. The deep reaction time of the carbonization reaction is 2–8 hours. The carbonization reaction temperature is 450–485°C. The heat treatment temperature is 450–485℃, and the heat treatment time is 1–2 hours.

2. The method for reducing the grindability index of raw coke according to claim 1, characterized in that, The amount of steam injected is 10 to 30 wt% of the carbonization raw material feed.

3. The method for reducing the grindability index of raw coke according to claim 1, characterized in that, The amount of heavy oil added is 5 to 15 wt% of the carbonization feedstock.

4. The method for reducing the grindability index of raw coke according to claim 1, characterized in that, The method described above for reducing the grindability index of raw coke yields a grindability index of 40–90 for the raw coke.